History of wireless telegraphy and broadcasting in Australia/Topical/Biographies/Robert Ballantyne Caldwell

Robert Ballantyne Caldwell Potted Biography Robert Ballantyne Caldwell Comprehensive Biography A comprehensive biography of Robert Ballantyne Caldwell has not yet been prepared for this Wikibook, however the following resources have been assembled in preparation: Research - Robert Ballantyne Caldwell - Summary of research to date Transcriptions and Notes - Robert Ballantyne Caldwell - More than 10 transcriptions (Reads like a biography) Photos, QSL cards and other graphics - Robert Ballantyne Caldwell - Nothing uploaded as yet, but many photos available in Trove Incubator of Wikipedia Article on Robert Ballantyne Caldwell - Coming real soon now! Key internet links: Brief wireless bio of Caldwell in 1929 AMATEUR STATIONS. 5BP — North Unley. OPERATOR R. B. CALDWELL. 5BP experimental wireless station is owned and operated by Mr. R. B. Caldwell, of 53 Hughes street, North Unley. Mr. Caldwell was perhaps the first to experiment in radio in this State, having first taken an active interest in 1902. Mr. Caldwell is president of the Wireless Institute of Australia (South Australian division), and has held that position for a number of years. His first experiments in radio were conducted with coherers and spark transmitters, and experimenting continued until the outbreak of war, when the Commonwealth Government closed all amateur stations. Immediately after the war came to an end he again conducted experiments, this time, however, having the advantage of new apparatus, and principles evolved for wartime communication. As soon as possible a valve was installed. This was a comparatively crude piece of apparatus, with a plate like a 50-watt transmitting tube. The elements were enclosed in a piece of heavy glass tubing. All the condensers, nuts, and bolts and other accessories used on the receiver were made by Mr. Caldwell. The set was mounted on a red-fibre panel. The first radiotelephone transmission picked up by Mr. Caldwell was from a ship visiting Port Pirie. The chief engineer of this vessel bought the transmitter in America, and during the voyage conducted transmissions. Mr. Caldwell's three-coil Armstrong receiver was later also used as a telephone transmitter, and an amateur a few streets away succeeded in picking up the transmission. This was followed by a 10-watt transmitter employing one UX210 valve as an oscillator. Various circuits have been experimented with, and transmissions from this station have been heard all over the State and by numbers of listeners in Victoria and New South Wales. Electrolytic rectifiers are employed, but "S" tubes are (Start Photo Caption) 5BP EXPERIMENTAL RADIO STATION — This station is owned and operated by Mr. R. B. Caldwell, one of the oldest experimenters in radio in this State. Mr. Caldwell is well-known as president of the Wireless Institute of Australia (South Australian Division). He has conducted some interesting tests with television. (End Photo Caption) also available for this purpose. Plate potential is at 500 volts. The receiver employed for 200 metre and broadcast reception uses the well-known tuned anode system. Shortwave reception is performed with an Armstrong three-coil circuit. Shortwave transmission is effected with a loose-couple Hartley arrangement, with one Philips TB04/10 as an oscillator. This transmitter has come into commission only recently, and will shortly be heard to good effect on the 40-metre band. Television is another branch of Mr. Caldwell's activity in the wireless world.http://nla.gov.au/nla.news-article58621663 AMATEUR STATIONS The Mail (Adelaide) 11, 895 South Australia 20 July 1929 13 April 2025 28 National Library of Australia Brief bio of Caldwell at the time of his retirement RAILWAY ENGINEER RETIRES. Mr. R. B. Caldwell's Career. Mr. R. B. Caldwell, who retired yesterday from the position of resident engineer in the Adelaide division of the South Australian railways, started work with the Irrigation Department in 1887. A few years later he became assistant to Mr. Oliver Rogers in the Engineer-in-Chiefs Department, and was connected with the construction of the Beetaloo waterworks, the Barossa dam, and the Outer Harbor. In 1909 Mr. Caldwell entered the railway service, and after some years on construction works, which included the bridge over the Port River, the Hilton overway bridge, and the Mile-End freight yard, he was appointed resident engineer for the Mile-End district, which position he occupied until Mr. W. A. Webb, the then Railways Commissioner, altered the system of control in 1923. From then he occupied the position of assistant superintendent, maintenance, on the Adelaide division, until 1932, when he became resident engineer of the same district. Mr. Caldwell was one of the pioneers in the use of arsenic for the poisoning of weeds on railway tracks, and developed the mechanical poison mixing train, which has saved much money in the application of poison on the South Australian railways. He has taken a practical interest in wireless, and later television, and was one of the first amateur broadcasters in South Australia. For many years he was president of the South Australian division of the Wireless Institute, and later became Federal president. Mr. Caldwell was one of the first to drive a motor car in this State, and is a keen amateur mechanic. His workshop at his residence, in Hughes street, North Unley, is particularly well equipped. He will be given a luncheon today by officers of the department.http://nla.gov.au/nla.news-article74095788 RAILWAY ENGINEER RETIRES The Advertiser (Adelaide) 16 February 1934 12 April 2025 25 National Library of Australia References